Means for the control of the feeding mechanism in sewing machines



June 17, 1952 Filed Feb. 16, 1946 A. B. E. KARLSSON ET AL MEANS FOR THE CONTROL OF THE FEEDING MECHANISM IN SEWING MACHINES 2 SHEETSSHEET l Inverziors, Amie/ 9 B.E. a/Z.$Jo7n AZZarz HE/L ksson MEANS FOR THE CONTROL OF THE FEEDING MECHANISM IN SEWING MACHINES Filed Feb. 16, 1946 2 SHEETS-SHEET 2 June 1952 A B. E. KARLSSON ET AL 2,600,544

Anders 8. E. lfarzsso AZZerr H. Erika-Jan Patented June 17, 1952 MEANS FOR THE CONTROL OF THE FEED- ING IWECHANISM IN SEWING MACHINES Anders Bertil Emanuel Karlsson and Allan Herman Eriksson, Huskvarna, Sweden, assignors to Husqvarna Vapenfabriks Aktiebolag, Huskvarna, Sweden, a corporation of Sweden Application February 16, 1946, Serial No. 648,184 In Sweden January 13, 1945 6 Claims. (Cl. 112210) The present invention refers to sewing machines, wherein the mechanism adapted together with the presser foot to move or feed the work piece during the sewing operation may be regulated in such manner that the direction of movement of the work piece may be reversed, and, if desired, also in such manner that the magnitude of the feeding steps or the length of stitch may be altered. The invention has primarily for its object to form that member or those members by means of which the feeding mechanism is operated, in such manner that a simple and convenient operation is rendered possible.

According to one feature of the invention, a lever is provided as an operating member to reverse the feeding direction. Hereby an extremely simple operation will be permitted, inasmuch as said lever only requires to be depressed, for example, to effect reversal.

If a variation of the length of the stitches and a reversal of the feeding direction are to be provided for at the same time, an arrangement according to the invention is primarily distinguished by the feature that an operating member for changing the length of the stitches is coupled to a member for the reversal of the feeding direction of the feeding mechanism, in a manner such that every position of adjustment of the operating member controlling the length of the stitches corresponds to a position for forward feeding and to a position for rearward feeding of the member adapted to reverse the feeding direction. The coupling between the two operating members may be effected by different means, a particularly advantageous form of embodiment with only a few and simple parts will be described in the following.

The embodiment shown in the accompanying drawings is intended as an elucidating example, and the invention is not limited to the details shown. The operating device may be combined with arbitrary suitable feeding mechanisms permitting an adjustment of the length of stitch and the direction of movement of the feeder, the mechanism shown in the drawing being thus only to be regarded as an example. Fig. 1 shows a feeding mechanism viewed from below. Fig. 2 is a vertical section on line II-l1 in Fig. 1. Figs. 3 and 4 are diagrammatic sketches of parts associated with the controlling member-of the feeding mechanism, said parts taking two different positions in the figures, respectively, Fig. 5 is a vertical section substantially on the broken 2 line VV in Fig. 1, and Figs. 6-8 show a detail of the lever in different positions.

The feeding mechanism comprised in the embodiment shown in the drawing is mounted underneath the table I of the sewing machine and receives its movement from a shaft 2 carried by bearings 3, 4 on the lower side of the table. This shaft is driven in any suitable manner, for instance by means of a shaft 5 projecting upwardly through the arm of the housing and by a bevelled gearing 6, I. In addition to the feeding mechanism, the shaft 2 may also be adapted to operate the shuttle of the sewing machine through arrangements which are not illustrated.

In the construction shown, the feeding mechanism consists of a feeder 8 on a carrier-arm 9, which is actuated by a rocking rod I 0 for the feeder. This rod is carried by bearings ll, l2 and is provided with an arm M, which is connected through .a link IE to an eccentric rod or strap l6 adapted to be actuated by an eccentric IT on the shaft 2. The link 15 is mounted at a point between the ends thereof on a pin [8 secured to a link arm l9. This arm is mounted with the other end thereof on a pin 20 secured to the one end of a crank 2| secured on a shaft 22. The shaft 22 is supported by a bearing 23 and also has another crank arm 24 secured thereon, with which an operating member in the form of a lever 25 is pivotally connected by means of a bolt 26.

The feeding mechanism just described may be varied in many respects as to the details thereof within the scope of the invention, provided it fits to the operating device to be described in the following, to which the invention refers primarily.

It will appear from Figs. 3 and 4 how different operating movements are transmitted to the feeding mechanism. If the pin 20 is located adjacent the link I 5, as in Fig. 2, no movement of the link [5 will be caused in the longitudinal direction thereof when the eccentric I! is rotated, by reason of which the rocking rod of the feeder remains stationary and consequently no feeding is taking place. The pin 20 may be adjusted, however, by means of the crank mechanism consisting of the arms 2|, 24 and the shaft 22, in a manner such that it will be outside the position indicated, that is to say below the link l5, as in Fig. 3, or above this link, as in Fig. 4. The initial position upon an adjustment is indicated in Figs. 3 and 4 by full lines, while the extreme position, into which the link I5 and the arm l9 swing at a rotary movement of the eccentric H is indicated by dotted lines. It will be seen immediately from the drawings that the link I5 moves from the initial position to the left into the extreme position (the arrow 30) according to Fig. 3, whereas it moves to the right between corresponding positions according to Fig. 4 (the arrow 3|). The rocking rod l0 of the feeder actuated by the link IE will consequently turn to and fro in opposite directions as compared with the movement of the eccentric I'I, according as the pin 26 is adjusted according to Fig. 3 or Fig. 4, which causes the carrier-arm 9 to impart a movement to the feeder 8 to feed the work forwardly in the one case (corresponding to Fig. 3), and a movement thereto for rearward feeding in the other case (corresponding to Fig. 4) In the position where the pin is opposite the link 15, no feeding will occur, that is to say, the length of stitch here equals naught, and it is obvious that by adjusting the pin 20 into arbitrary positions within certain ranges above and below the link l5 it will be possible to vary the feeding so that any feeding steps may be obtained within corresponding limits by means of the feeder, arbitrary lengths of the stitches being thus also obtained in forward as well as in rearward feed- The said adjustment of the crank device may be performed by means of the operating device to which the invention primarily refers. According to the invention, the operating member is formed as a lever with a depressing button 32 outside the housing 29 of the sewing machine, which is provided with a slit 34 having the lever rod proper extending therethrough. The lever is coupled to the feeding mechanism in such manner that the feeding direction is reversed from forward feeding to rearward feeding by depression of the lever, while for reversal in the opposite direction there is provided a spring releasable through other actuation of the lever. Such a spring may. be. arranged in any suitable position in the motion-transmitting connection between the lever and the arm 2i, provided ithas an effect. such as to tend to move the lever outwardly. Such a spring is shown in Fig. 1 in the form of a helical spring 35, which is coiled concentrically about the shaft 22 and secured with the ends thereof in such manner as to tend to turn the crank device in the desired direction.

The direction of movement is reversed by means of the lever, but the latter is coupled to a member for changing the, length of stitch in such manner that every position of adjustment of this member corresponds to a position for forward feeding and to a position for rearward feeding of the lever, that is to say, it will be possible in every stitch-length-position to reverse the direction of movement of the feeder in order thus to sew in the opposite direction with the length of stitch maintained. In the construction shown, the coupling is effected by means of a cam member 35 (Fig. 5) cooperating with the lever. The cam member is provided with two curves or cam surfaces 31, 38 disposed symmetrically in relation to a plane perpendicular to the axis about which the cam member is rotatable. The cam member is secured on a shaft 39, which is mounted in a bore in the wall 29 of 'themachine housing and carries a hand wheel 49 on the outer end thereof. The lever carries a projection ll, which contacts the outer curve 38 by the resilient force acting outwardly in the longitudinal direction of the lever. When the hand wheel is turned from the zero-position shown in Fig. 5, the curve 38 will move so that the lever is displaced outwardly. Such a position of the lever and curve is shown in Fig. 5 and more diagrammatically in the fragmentary Fig. 6 and corresponds to forward feeding by means of the feeder. The projection may also be moved and kept in engagement with the inner curve 31, however. Provided on the lever is a detent 42, which upon depression of the lever into the position shown in Fig. '7 may be adjusted behind a locking edge 43 when the lever is depressed, so that the detent takes the position shown in Fig. 8. The locking edge as and the inner curve 31 extend in parallel, and when the hand wheel is turned in the new position of the lever, the projection will follow the curve 31, so that the lever is displaced inwardly from the zero-position shown in Fig. 5.

As to the mode of operation of the operating member the following might be further stated:

The spring 35 acts in such manner as to tend normally to keep the projection H pressed against the outer curve 38. The lever rod then bears with its upper edge against the edge of the upper end of the slit 34 in the wall of the machine housing. In this position of the lever, the pin 29 actuated by the crank device is in one of a number of possible positions, i. e. in the position shown in Fig. 3, that is to say, the feeding mechanism is adjusted for forward feeding of the work piece. The length of stitch may be varied continuously from zero to a maximum value by turning the hand wheel 40. When the length of stitch is naught, the projection 41 will be at the point where the distance between the curves 31, 38 is the least, and the length of stitch is increased, according as the hand wheel is turned so that the distance between the curves increases at the point where the projection is located. An efiort to depress the lever from the position shown in Fig. 5 with the projection at thenarrowest point between the curves has no effect; here the length of stitch is naught for both curves. In other angular positions of the cam member, the lever may be pressed inand locked to the inner curve 31 by simultaneous depression. This is facilitated by the fact that the lever button is set obliquely to the lever rod and has its upper side directed obliquely upwards, as shown in Fig. 5.

What we claim is:

1. In a sewing machine a device for controlling the movement of the feeding mechanism comprising a member for shifting the feeding direction of the feeding mechanism, a cam member against which the shifting member is in contact and provided with a cam surface for forward feed and with a cam surface for backward feed said cam surfaces being alternately engageable by the shifting member, a spring adapted to keep the shifting member in engagement with one of said cam surfaces, a detent on the feed shifting member adapted to cooperate with a locking edge on the cam member to couple the shifting member to the cam member on depression of the latter against the action of the spring, and means to operate the cam member to set the feed shifting member in various positions corresponding to various feeding lengths.

2. In a sewing machine a device for controlling the movement of the feeding mechanism according to claim 1 in which the operating means for the cam member comprises a hand wheel,

and the feed shifting member comprises a depressable lever.

3. In a sewing machine a device for controlling the movement of the feeding mechanism according to claim 1 in which the operating means for the cam member comprises a hand wheel, and the shifting member comprises a depressable lever comprising a rod and a button mounted at the end of said rod, the end surface of the button extending obliquely to the longitudinal direction of the rod.

4. In a sewing machine means for the control of the feeding mechanism comprising a lever for the reversal of the feeding direction of the feeding mechanism, means to connect the lever with the feeding mechanism to change the feeding direction from forward to backward feed when depressing the lever, a spring actuating the lever in the opposite direction to reverse the feeding direction from backward to forward feed on release thereof, a cam member adapted for cooperation with the lever, means to couple the lever to the cam member, and means to rotate the cam member engaged by the lever for displacing the lever continuously to various positions corresponding to various stitch lengths.

5. In a sewing machine a device for controlling the movement of the feeding mechanism comprising a lever for the reversal of the feeding direction of the feeding mechanism, a cam member against which the lever is in contact and provided with a cam surface for forward feed and a cam surface for backward feed, the lever being adjustable to engage one or the other of said cam surfaces, means to couple the lever to the cam member, and means to rotate the cam member engaged by the lever for displacing the lever continuously to various positions corresponding to various stitch lengths.

6. In a sewing machine means for the control of the feeding mechanism of the machine comprising a lever for the reversal of the feeding direction of the feeding mechanism, means to connect the lever with the feeding mechanism said means comprising a bell crank device adapted to be set by the lever into different positions corresponding to forward feed, as a result of depressing the lever to move it longitudinally in one direction, a spring actuating the lever in the opposite direction to reverse the feeding direction from backward to forward, a cam member engaging the lever, means to couple the lever to the cam member, and means to rotate the cam member engaged by the lever for displacing the lever continuously to various positions corresponding to various stitch lengths.

ANDERS BERTIL EMANUEL KARLSSON. ALLAN HERMAN ERIKSSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,014,298 Gray Jan. 9, 1912 1,118,271 Diehl et a1 Nov. 24, 1914 1,477,264 Hleb Dec. 11, 1923 

